The effect of extracorporeal electromagnetic shock waves on the morphology and contractility of rabbit ureter

Abstract

Purpose: Although extracorporeal shock wave lithotripsy (ESWL) is known to cause pathologic changes in various organs, little is known about its effects on the ureter, the target organ in ESWL of ureteral stones in situ. In this study, we sought to determine the short-term effects of ESWL on the ureter.

Materials and methods: Left lower ureteral segments of 21 rabbits were removed to serve as the control group and 2000 shocks were applied to the right lower ureters. Groups of 7 rabbits were sacrificed 1, 3 and 5 days after shock wave exposure. While histomorphological alterations were examined under light and transmission electron microscopy, contractility of all ureters was determined in organ baths.

Results: The epithelial cells disclosed no change after shock wave application. Histologically the muscular layer was the most affected part of the ureter. There was interstitial and intracellular edema on light microscopy and marked chromatin and mitochondrial changes at the subcellular level. The adventitial layer was also edematous. These changes were prominent on days 1 and 3 and returned to normal on day 5. The contractility of the ureters on day 1 was significantly reduced (p < 0.05). However, the contractility of the samples on days 3 and 5 were not significantly different from controls.

Conclusion: Our findings demonstrate that electromagnetic shock waves produce reversible morphological and functional changes in rabbit ureteric muscle.